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Diffstat (limited to 'drivers/iommu/of_iommu.c')
-rw-r--r--drivers/iommu/of_iommu.c107
1 files changed, 55 insertions, 52 deletions
diff --git a/drivers/iommu/of_iommu.c b/drivers/iommu/of_iommu.c
index 40f57d293a79..6b989a62def2 100644
--- a/drivers/iommu/of_iommu.c
+++ b/drivers/iommu/of_iommu.c
@@ -17,32 +17,23 @@
#include <linux/slab.h>
#include <linux/fsl/mc.h>
-#define NO_IOMMU 1
+#include "iommu-priv.h"
static int of_iommu_xlate(struct device *dev,
struct of_phandle_args *iommu_spec)
{
const struct iommu_ops *ops;
- struct fwnode_handle *fwnode = &iommu_spec->np->fwnode;
int ret;
- ops = iommu_ops_from_fwnode(fwnode);
- if ((ops && !ops->of_xlate) ||
- !of_device_is_available(iommu_spec->np))
- return NO_IOMMU;
+ if (!of_device_is_available(iommu_spec->np))
+ return -ENODEV;
- ret = iommu_fwspec_init(dev, &iommu_spec->np->fwnode, ops);
+ ret = iommu_fwspec_init(dev, of_fwnode_handle(iommu_spec->np));
if (ret)
return ret;
- /*
- * The otherwise-empty fwspec handily serves to indicate the specific
- * IOMMU device we're waiting for, which will be useful if we ever get
- * a proper probe-ordering dependency mechanism in future.
- */
- if (!ops)
- return driver_deferred_probe_check_state(dev);
- if (!try_module_get(ops->owner))
+ ops = iommu_ops_from_fwnode(&iommu_spec->np->fwnode);
+ if (!ops->of_xlate || !try_module_get(ops->owner))
return -ENODEV;
ret = ops->of_xlate(dev, iommu_spec);
@@ -61,7 +52,7 @@ static int of_iommu_configure_dev_id(struct device_node *master_np,
"iommu-map-mask", &iommu_spec.np,
iommu_spec.args);
if (err)
- return err == -ENODEV ? NO_IOMMU : err;
+ return err;
err = of_iommu_xlate(dev, &iommu_spec);
of_node_put(iommu_spec.np);
@@ -72,7 +63,7 @@ static int of_iommu_configure_dev(struct device_node *master_np,
struct device *dev)
{
struct of_phandle_args iommu_spec;
- int err = NO_IOMMU, idx = 0;
+ int err = -ENODEV, idx = 0;
while (!of_parse_phandle_with_args(master_np, "iommus",
"#iommu-cells",
@@ -107,24 +98,37 @@ static int of_iommu_configure_device(struct device_node *master_np,
of_iommu_configure_dev(master_np, dev);
}
-const struct iommu_ops *of_iommu_configure(struct device *dev,
- struct device_node *master_np,
- const u32 *id)
+static void of_pci_check_device_ats(struct device *dev, struct device_node *np)
{
- const struct iommu_ops *ops = NULL;
struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
- int err = NO_IOMMU;
- if (!master_np)
- return NULL;
+ if (fwspec && of_property_read_bool(np, "ats-supported"))
+ fwspec->flags |= IOMMU_FWSPEC_PCI_RC_ATS;
+}
- if (fwspec) {
- if (fwspec->ops)
- return fwspec->ops;
+/*
+ * Returns:
+ * 0 on success, an iommu was configured
+ * -ENODEV if the device does not have any IOMMU
+ * -EPROBEDEFER if probing should be tried again
+ * -errno fatal errors
+ */
+int of_iommu_configure(struct device *dev, struct device_node *master_np,
+ const u32 *id)
+{
+ bool dev_iommu_present;
+ int err;
- /* In the deferred case, start again from scratch */
- iommu_fwspec_free(dev);
+ if (!master_np)
+ return -ENODEV;
+
+ /* Serialise to make dev->iommu stable under our potential fwspec */
+ mutex_lock(&iommu_probe_device_lock);
+ if (dev_iommu_fwspec_get(dev)) {
+ mutex_unlock(&iommu_probe_device_lock);
+ return 0;
}
+ dev_iommu_present = dev->iommu;
/*
* We don't currently walk up the tree looking for a parent IOMMU.
@@ -140,37 +144,29 @@ const struct iommu_ops *of_iommu_configure(struct device *dev,
pci_request_acs();
err = pci_for_each_dma_alias(to_pci_dev(dev),
of_pci_iommu_init, &info);
+ of_pci_check_device_ats(dev, master_np);
} else {
err = of_iommu_configure_device(master_np, dev, id);
}
+ if (err && dev_iommu_present)
+ iommu_fwspec_free(dev);
+ else if (err && dev->iommu)
+ dev_iommu_free(dev);
+ mutex_unlock(&iommu_probe_device_lock);
+
/*
- * Two success conditions can be represented by non-negative err here:
- * >0 : there is no IOMMU, or one was unavailable for non-fatal reasons
- * 0 : we found an IOMMU, and dev->fwspec is initialised appropriately
- * <0 : any actual error
- */
- if (!err) {
- /* The fwspec pointer changed, read it again */
- fwspec = dev_iommu_fwspec_get(dev);
- ops = fwspec->ops;
- }
- /*
- * If we have reason to believe the IOMMU driver missed the initial
- * probe for dev, replay it to get things in order.
+ * If we're not on the iommu_probe_device() path (as indicated by the
+ * initial dev->iommu) then try to simulate it. This should no longer
+ * happen unless of_dma_configure() is being misused outside bus code.
*/
- if (!err && dev->bus && !device_iommu_mapped(dev))
+ if (!err && dev->bus && !dev_iommu_present)
err = iommu_probe_device(dev);
- /* Ignore all other errors apart from EPROBE_DEFER */
- if (err == -EPROBE_DEFER) {
- ops = ERR_PTR(err);
- } else if (err < 0) {
+ if (err && err != -EPROBE_DEFER)
dev_dbg(dev, "Adding to IOMMU failed: %d\n", err);
- ops = NULL;
- }
- return ops;
+ return err;
}
static enum iommu_resv_type __maybe_unused
@@ -191,7 +187,7 @@ iommu_resv_region_get_type(struct device *dev,
if (start == phys->start && end == phys->end)
return IOMMU_RESV_DIRECT;
- dev_warn(dev, "treating non-direct mapping [%pr] -> [%pap-%pap] as reservation\n", &phys,
+ dev_warn(dev, "treating non-direct mapping [%pr] -> [%pap-%pap] as reservation\n", phys,
&start, &end);
return IOMMU_RESV_RESERVED;
}
@@ -225,7 +221,7 @@ void of_iommu_get_resv_regions(struct device *dev, struct list_head *list)
* that represent reservations in the IOVA space, which are regions that should
* not be mapped.
*/
- if (of_find_property(it.node, "reg", NULL)) {
+ if (of_property_present(it.node, "reg")) {
err = of_address_to_resource(it.node, 0, &phys);
if (err < 0) {
dev_err(dev, "failed to parse memory region %pOF: %d\n",
@@ -254,7 +250,14 @@ void of_iommu_get_resv_regions(struct device *dev, struct list_head *list)
phys_addr_t iova;
size_t length;
+ if (of_dma_is_coherent(dev->of_node))
+ prot |= IOMMU_CACHE;
+
maps = of_translate_dma_region(np, maps, &iova, &length);
+ if (length == 0) {
+ dev_warn(dev, "Cannot reserve IOVA region of 0 size\n");
+ continue;
+ }
type = iommu_resv_region_get_type(dev, &phys, iova, length);
region = iommu_alloc_resv_region(iova, length, prot, type,
generated by cgit (git 2.34.1) at 2025-12-25 12:53:55 +0000